Method of lining concrete sewers, ducts, and containers



Aug. 17 1926. l,596;107

l.. P. KQVANDA ET A.

METHOD OF LINING CONCRETE SEWERS, DUCTSl AND CONTAINERS Filed Dec. 16, 1925 Patented Aug. 17, 1926i..

LOUIS-P. IKOVANDA .AND JAY: H. HUBBELL, 0F

LOS ANGELES, CALIFORNIA..

METHOD 0F LININGr CONCRETE SEWERS, DUCTS, AND CONTAINERS.

Application led December 16, 1925. Serial No. 75,694.

Our invention relates to a method of lining concrete-sewers, ducts, and containers, and has for its principal object the provision of a relatively simpleA and easily practicedv method Vof providingt'ducts and containers that are formed of concrete or like material with an acid-proof lining in order that the inner surface of the duct or container will be thoroughly protected against the action of deleterious liquids, gases, and thelike.

It will be understood that where it is desired to protect the inner surfaces of con- Crete sewers and the ducts and containers for Vcertain liquids against the destructive action of certain gases and liquids, it is the present general practice to line the concrete structures with vitrified clay tile or blocks and to render such lining thoroughly acidproof, it is necessary to fill the joints between the lining tiles or blocks `with some acidproof material. If the joints between the lining tile or blocks are not filled with some inert material, the concrete back -of the joints and lining blocks will be attacked by destructive acids and gases through the joints and ina short time the lining members will become loose and drop from their place in the structure, thereby not only exposing the concrete body of the sewer or contalner to the destroying elements, but also obstructing the free iiow of sewage or 1i uid through the duct or sewer.

o iill the joints between the vitriiied clay lining tile or blocks with an inert acid-proof material is impractical from an economical standpoint inasmuch as' the filling of such joints .involves considerable time, labor, material, and consequent expense.

It is one of the purposes of our invention to simplify and cheapen the cost of construction of lined concrete structures and to do away with the necessity of the expensive and practically useless segmental vitrified clay lining tile or blocks now generally used in the construction of sewers and the like and to accomplish our objectwe propose to providea continuous and jointless lining of acid-proof materials for ducts and containers that are formed of concrete and which continuous lining is of suchnature as to af,- ford complete protection for the concrete against the destructive action of sewage,

lapproximately 50% gases, liquids and the like, and which latter are highly detrimental to the life of the concrete where the latter is not protected.

A .further object of our invention is to provide a protective lining and method of applying s ame whereby said linin forms an integral part of the structure so tat it will not flake, disintegrate and fall off as would be the case if lining materials such as asphaltic or tar paints were used.

With the foregoing and other objects in View our invention consists in certain features of novelty hereinafter more fully de'- scribed and claimed and illustrated in theaccompanying drawings, in which- Fig. l is a perspective view of a concrete sewer in the process of construction and the upper or arch portion of which is lined in accordance with our improved method.

Fig. 2 is a cross sectional view of the completed sewer with the lining applied thereto.

Fig. 3 is a perspective view of a form for reducing pre-cast sewery pipe and which atter is lined with the continuous acidproof material in accordance with our invention.

Fig. 4 is a sectional view showin the method employed in bonding parts o our improved lining to one another.

Fi 5 is a detailed section of a portion of a joint between sections of pre-cast sewer pipe and showing the arrangement of thev ming therein. In lining of the type sheet metal forms 10 for producing the upper or arched pxortion of the sewer are arranged in the c annel portion of the invert monolithic sewer structures -or base 11 of the sewer. and before the concrete that forms the upper or arched ortion of the sewer is applied to the arc ed form 10, the upper or outer surface of said form 10 has applied thereto in any suitable manner a layer l2 of inert acid-proof material, preferably a compoundconsisting of sulphur and 50% ne sand well graded to give maximum strength. This lining compound is placed on the form while in molten condition and we have found that said lining material can be very quickly and evenly distributed on the form by spraying the same from a molten material spraying apparatus of the type disclosed described in Figs. 1 and 2, the.

in our copending application for U. S. Let-- ters Patent filed October 1, 1925, Serial No. 59,821.

The molten material when sprayed onto the form 10 sets very quickly and thus the entire lining is practically one homogeneous mass in the form of a layer or sheet of substantial thickness and entirely devoid of joints. Atthe end of a working period the edge of. the molten lining material sprayed onto the form 10 is tapered or beveled off as designated by 13 in Fig. 1, and when the work of *applying the lining compound is continued, the molten material applied from the spraying apparatus will soften the tapered portion 13 previously applied to a suiiicient degree to form a perfect joint thus eliminating joints and making the entire lining practically continuous.

After the acid-proof lining has been thus applied to the form 10 the upper or arched portion 14 of the sewer structure is applied directly over the lining and the concrete forming the arch portion of the sewer and the lining 12,l both being composed wholly of mineral substances, will produce a perfect bond so that the lining is practically an integral part` of the sewer body.

In Figs. 1 and 2 we have shown the upper or arched portion only of the sewer as being provided with thev acid-proof lining contemplated by our invention, but it will be .understoodthat if desired the lining material'may be applied to the surface of the channel 1n the base or invert '11 thereby affording complete protection for all portions of the inner surface of the sewer.

When our improved lining is applied to pre-cast sewer pipe, the outer surface of a tubular or cylindrical form 15 is'covered or coated with the lining-'material while the latter is in molten condition and when said 'material has become set the coated form is concentrically arran ed within an outer tubular form 16 and t e concrete body 17 of the sewer pipe is poured into the space between the outer form and the coated inner form. When the concrete has become set and hard the forms are removed and thus lined sewer pipe section is produced.

In the event that the lining is applied to pre-cast sewer pipes having bell orflanged ends, the .linings terminate short distances from the ends of the pipe sections as shown in Fig. 5, and when pipe sections are assembled, the' annular grooves between the ends of the linings are tilled 'with molten lining material, thereby providing a practically continuous acid-proof lining.

ln the event that a concrete sewer or ductv is laid in soil that contains alkali or other agent that might act on the concrete with injurious resultsci the entire exterior surface of the sewer of uct may be given a protective coatlng oi the sulphur-silica compound,

vforms the body the latter being applied in any suitable manner, preferably by spraying.

Thus it will be seen that we have provlded a relatively simple, practical and economical ing an inert acid-proof compound to a form while in plastic condition and when said lining material has becomeset,` a pl ing thereto `the concrete that forms the Ibedrijf of the completed structure.

2. The herein described method of lining monolithic sewers, ducts, and containers, which consists in applying to a form a layer of molten acid-proof material and when said molten material has become set, applying thereto the concrete that forms the body of the monolithic structure.

3. The herein described method of providing concrete sewers, ducts', and containers, with an acid-proof lining which consists in producing a layer of acid-proof material that corresponds to the form of the.inner surface of the completed structure and then applying to said layer of acid-proof material the concrete that forms the body of the completed structure.

4. The herein described method of providing monolithic sewers and containers with acid-proof linings which consists in shaping a molten silica-sulphur compound to correspond with the form of the inner surface of the monolithic structure and then applying ,to the formed silica-sulphur lining structure the concrete that forms the body of the completed structure.

5. The herein described method of rendering the inner surfaces of concrete ducts and containers acid-proof which consists in .forming a lining layer of inert acid-proof ,material while the same is in plastic condition and when said lining layer has become set, applying thereto the concrete that forms the body ot the completed structure.

6. The herein described method of rendering the inner surfaces of concrete ducts and containers acid-proof which consists in forming a lining layer of sulphur-silica compound while the same is in molten condition and when said lining layer has become set, applying thereto the concrete that of the completed structure.

7. The herem described method of lining monolithic ducts and containers which consists in applying to a, form a lining layer' of sulphur-silicaJ compound while the same is in molten condition and' when said lining layer has become set, applying thereto the concrete that foi'msl the body of the com-4 pleted monolithic structure.

8. The Vherein described method of lining monolithic ductshnd containers which con` v sists in applying to a form a jointless homo and when gepeous lining layer of sulphur-siliceJ com- 10 pound while the same is in molten condition said ,lining layer has become set, applying thereto the concrete that forms the body of the complete monolithic structure.l

In testimony whereof we aix oursign natures. v

LOUIS P. KOVANDA. JAY H.- I-IUBBELL1 Y 

